egrep/fgrep/grep is a line-oriented tool. The regular expression will NEVER span across lines because grep operates one line at a time.
The reason the regular expression with the bracket expression [^"\n] does not match "What uncouth dialect is that?" is because within the bracket expression the backslash ceases to be a special character; the sequence \n in [^"\n] does not represent a newline character, but a forward slash and an n, two separate characters. Since this translates to any character that is not a quote, backslash, or n, the n in "uncouth" prevents the match from ocurring.
For the nitty gritty on bracket expressions, refer to Regular Expressions, from which the following is extracted:
Quote:
Originally Posted by POSIX
The special characters '.', '*', '[', and '\' (period, asterisk, left-bracket, and backslash, respectively) shall lose their special meaning within a bracket expression.
Hello,
I want to compare two files. All records in file 2 that are not in file 1 should be output to file 3.
For example:
file 1
123
1234
123456
file 2
123
2345
23456
file 3 should have
2345
23456
I have looked at diff, bdiff, cmp, comm, diff3 without any luck! (2 Replies)
hi all,
i want to do this shell script.
create a script that will check the transferred file vs. orig file.
1. diff the file1 and file2
2. if difference found, retain the original file and email to netcracker team.
3. if no difference found, delete the previous file and retain... (3 Replies)
Hi,
svn diff does not work very well with 2 local folders, so I am trying to do this diff using diff locally.
since there's a bunch of meta files in an svn directory, I want to do a diff that excludes everything EXCEPT *.java files. there seems to be only an --exclude option, so I'm not sure... (3 Replies)
OS : SuSE Linux 10 (zOS)
I create two files test1 and test2
/home/me # more test1
1 2 3 4 5
/home/me # more test2
1 2 3
I entered the following command on cronjob and its work
diff /home/me/test1 /home/me/test2 > /home/me/test3
its created test3.
But the output of test3 is as... (1 Reply)
Hi,
I am new to shell scripting.
please help me to find out the solution.
I need a script where we need to read the text file(consists of all file names) and get the file names one by one
and append the date suffix for each file name as 'yyyymmdd' .
Then search each file if exists... (1 Reply)
Hi I have a file like this
I need to delete all the lines between SQ and // and not the lines containing them.
So the desired output should be
I tried by using flip-flop operator
perl -wlne 'print if !(/SQ/../\/\//)'But its not printing the lines containing regexes.
Thanks in advance:b: (4 Replies)
Guys i have 3 files,
but i want to compare and diff only the 2nd column
path=`/home/whois/doms`
for i in `cat domain.tx`
do
whois $i| sed -n '/Registry Registrant ID:/,/Registrant Email:/p' > $path/$i.registrant
whois $i| sed -n '/Registry Admin ID:/,/Admin Email:/p' > $path/$i.admin... (10 Replies)
I am working on a multilingual dictionary and I have data in three columns. The data structure can be
word=word=gloss
or
word word=word word=gloss gloss
= acts as a delimiter
The number of words separated by the delimiter can be up to 8 or 10. The structure is well defined in the sense... (6 Replies)
Discussion started by: gimley
6 Replies
LEARN ABOUT BSD
grep
GREP(1) General Commands Manual GREP(1)NAME
grep, egrep, fgrep - search a file for a pattern
SYNOPSIS
grep [ option ] ... expression [ file ] ...
egrep [ option ] ... [ expression ] [ file ] ...
fgrep [ option ] ... [ strings ] [ file ]
DESCRIPTION
Commands of the grep family search the input files (standard input default) for lines matching a pattern. Normally, each line found is
copied to the standard output. Grep patterns are limited regular expressions in the style of ex(1); it uses a compact nondeterministic
algorithm. Egrep patterns are full regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space.
Fgrep patterns are fixed strings; it is fast and compact. The following options are recognized.
-v All lines but those matching are printed.
-x (Exact) only lines matched in their entirety are printed (fgrep only).
-c Only a count of matching lines is printed.
-l The names of files with matching lines are listed (once) separated by newlines.
-n Each line is preceded by its relative line number in the file.
-b Each line is preceded by the block number on which it was found. This is sometimes useful in locating disk block numbers by con-
text.
-i The case of letters is ignored in making comparisons -- that is, upper and lower case are considered identical. This applies to
grep and fgrep only.
-s Silent mode. Nothing is printed (except error messages). This is useful for checking the error status.
-w The expression is searched for as a word (as if surrounded by `<' and `>', see ex(1).) (grep only)
-e expression
Same as a simple expression argument, but useful when the expression begins with a -.
-f file
The regular expression (egrep) or string list (fgrep) is taken from the file.
In all cases the file name is shown if there is more than one input file. Care should be taken when using the characters $ * [ ^ | ( ) and
in the expression as they are also meaningful to the Shell. It is safest to enclose the entire expression argument in single quotes ' '.
Fgrep searches for lines that contain one of the (newline-separated) strings.
Egrep accepts extended regular expressions. In the following description `character' excludes newline:
A followed by a single character other than newline matches that character.
The character ^ matches the beginning of a line.
The character $ matches the end of a line.
A . (period) matches any character.
A single character not otherwise endowed with special meaning matches that character.
A string enclosed in brackets [] matches any single character from the string. Ranges of ASCII character codes may be abbreviated
as in `a-z0-9'. A ] may occur only as the first character of the string. A literal - must be placed where it can't be mistaken as
a range indicator.
A regular expression followed by an * (asterisk) matches a sequence of 0 or more matches of the regular expression. A regular
expression followed by a + (plus) matches a sequence of 1 or more matches of the regular expression. A regular expression followed
by a ? (question mark) matches a sequence of 0 or 1 matches of the regular expression.
Two regular expressions concatenated match a match of the first followed by a match of the second.
Two regular expressions separated by | or newline match either a match for the first or a match for the second.
A regular expression enclosed in parentheses matches a match for the regular expression.
The order of precedence of operators at the same parenthesis level is [] then *+? then concatenation then | and newline.
Ideally there should be only one grep, but we don't know a single algorithm that spans a wide enough range of space-time tradeoffs.
SEE ALSO ex(1), sed(1), sh(1)DIAGNOSTICS
Exit status is 0 if any matches are found, 1 if none, 2 for syntax errors or inaccessible files.
BUGS
Lines are limited to 256 characters; longer lines are truncated.
4th Berkeley Distribution April 29, 1985 GREP(1)